Renal lymphoma on a CAT scan

CAT is another name for CT. Imaging may show kidney enlargement, one or more masses, tissue around the kidney or changes elsewhere in the body. Doctors combine those observations with blood tests and usually tissue analysis before deciding on treatment.

Lymphoma begins in cells of the lymphatic and immune systems and can involve organs outside lymph nodes, including the kidneys. Kidney involvement does not automatically mean a separate kidney cancer. The lymphoma subtype and its distribution across the body are central to treatment planning.

CT appearances may overlap with kidney infection, inflammation and other tumours. A PET-CT scan can show metabolically active areas and help select a safe biopsy site. A pathologist then examines sampled tissue to identify whether lymphoma is present and determine its subtype.

A haematology or oncology team may request blood counts, kidney function tests, urine tests, imaging and a biopsy. Bring a current medicine list and report reduced urine, swelling, fever, flank discomfort, night sweats or unexpected weight loss. Kidney function can influence the choice and dosing of medicines.

Treatment is based on the lymphoma subtype, affected sites, symptoms, kidney function and overall health. Chemotherapy, immunotherapy or combinations may be considered. Radiotherapy, CAR T-cell therapy or autologous stem cell transplant have roles in selected circumstances; none is chosen from the CT appearance alone.

Seek urgent medical care if urine output falls markedly, you cannot pass urine, breathlessness develops, swelling increases quickly, or you become confused or unusually drowsy. These symptoms can accompany impaired kidney function or another serious problem.

During treatment, follow the team's emergency instructions for fever, chills, uncontrolled vomiting, bleeding or sudden weakness. Contact the service promptly rather than waiting for a scheduled visit, because cancer therapy can reduce the body's ability to respond to infection.

Ask whether the kidney finding is likely part of lymphoma elsewhere, which site will be biopsied and how kidney function affects the plan. Clarify the lymphoma subtype, treatment aim, expected monitoring and whom to contact for fever or reduced urine between appointments.